Improvement in lifting-jacks



.0. GAILLARD, r.

LIFTING-JACK.

Patented Feb. 27, 187-7.

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CHARLES GAILLARD, JR, OF ERIE, PENNSYLVANIA.

IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 187,707, dated February 27, 1877; application filed January 13, 1877.

To all whom it may concern:

Be it known that I, CHAS. 'GAILLABD, Jr.,.of Erie, in the county of Erie and State of Pennsylvania, have invented certain new and useful Improvements in Lifting-Jacks; and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention consists in a lifting-jack combining two methods of adjustment, one being by means of a screw-post perforated with holes for the reception of a pin, which passes through the stock, carrying a pedestal and operated within the body of the jack from the bottom, and the other by means of a sliding crotch operated by a togglejoint lever placed within the body of the jack, the effect being that the jack may be adjusted by means of the screw-post to the desired height and the crotch elevated by lever the required distance, as will be hereinafter more fully set forth.

In order to enable others skilled in the art to which my invention appertains to make and operate the same, I will now proceed to describe its construction, reference being had to the accompanying drawings, in which- Figure 1 is a partly sectional elevation, and Fig. 2 a central vertical section.

A represents the stock or body of the jack,

I the lower end of which is socketed and a screw-thread formed in said socket, in which fits a screw-post, B, perforated by a series of holes for the purpose of locking the post when adjusted to the proper position. This post carries a suitable base or pedestal, 0, upon which the jack rests. By turning this screwpost the jack is raised or lowered, as desired. A pin, a, is passed through the stock A and one of the holes in said post to lock it in its difierent given elevations. D is the crotch or rest, having a suitable slideway within the stock A and jointed to a lever, E, whichf'latter is jointed to an arm, F, and this arm is jointed to the stock, the said arm and lever forming a toggle-joint with the crotch.

The crotch, arm, and lever in their normal condition are shown in Fig.1, and in Fig. 2 they are shown in use. It will be observed that the lever E has been thrown back a little past a straight line with the crotch resting against the side of the stock, thereby retaining its position without further locks, catches, or other fastenings, the pressure being suffi cient.

This improved jack is used thus: It is given the required length or height to be used in connection with the article to be lifted by adjusting the screw farther in or out of the socketed stock, and locked with the pin, and having been placed in position with respect to the said article, so that the article will be beneath the point from which the article is to be raised, the lever is depressed until it is brought into the position shown in Fig. 2, when the crotch will have come to a fixed position and will sustain the load upon it. A very simple and effective jack is thus produced.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

A lifting-jack, constructed as hereinbefore described, composed of a stock,lA, a perforated elevating-post, B 0, pin a, and a crotch, D, with toggle-jointed lever E F arranged within the stock, substantially as shown and described.

In testimony that I claim the foregoing as my own, I affix my signature in presence of two witnesses.

CHARLES GAILLARD, JR.

Witnesses:

SAM. Woon, EZRA RHODES. 

